1995 OPEN FORUM Abstracts
Comparison Of Flutter^® To Positive Expiratory Pressure (Pep) Valves: A Laboratory Study
James B. Fink, MS, RRT., Ed Belingon, RRT., Hines VA Hospital and Loyola Univ. Chicago, Stritch School of Medicine, Hines IL, USA
Several devices have been recently approved by the FDA for use in airway clearance with scant data demonstrating physical effects of the devices on airway and lung mechanics. AARC clinical guidelines for Positive Airway Pressure differentiates fixed orifice (FO) resistors (PEP) from threshold (TH) resistors. The aim of this study was to better characterize these two types of resistors as well as the new Flutter^® valve (Scandipharm). We compared the Flutter^® (Scandipharm) to a threshold (Vital Signs) and a fixed orifice (Mercury Medical) resistors, to determine effects on airway pressure patterns, peak expiratory flows (PEFR; L / min), peak expiratory pressure (P_{exp;} cmH_2O), mean airway pressures (MAP;cmH_2O), work of breathing (W_{pt;}Joule / L) and changes in residual volume (RV; ml above baseline) during passive exhalation (V_T 500 ml, PIF 40 L / min) on a test lung with compliance of 0.02 cmH_2O / L. A comparison of the Flutter with TO and FO resistors (at the same relative orifice size) are shown below:
PEFRP_{exp} EPAPW(pt) MAPRV
FLUTTER 27.118.88.41.406 7.5 450
TH 10 cmH_2O 39 15.57.51.255 6.6 450
TH 15 cmH_2O 40 20.6 12.5 1.6949.9 700
FO 4.0 mm 23.7 9.50.30.7380.80
FO 3.0 mm 13.410.20.30.7141.60
FO resulted in lower PEFR, P_{exp}, W(pt) and RV than TH or Flutter (p < .001). The Flutter is similar to the threshold resistor in P_{exp}, EPAP, W(pt), MAP and RV.
We conclude that the characteristics of the FO as a PEP device are sufficiently different from TH and Flutter to be differentiated from EPAP (TH) or Flutter when used in clinical applications and studies.
OF-95-155